import optparse
from socket import *
from threading import *

screenLock = Semaphore(value=1)
def connScan(tgtHost, tgtPort):
	try:
		connSkt = socket(AF_INET, SOCK_STREAM)
		connSkt.connect((tgtHost, tgtPort))
		connSkt.send('ViolentPython\r\n')
		results = connSkt.recv(100)
		screenLock.acquire()
		print '[+]%d/tcp open' % tgtPort
		print '[+] ' + str(results)
	except:
		screenLock.acquire()
		print '[-]%d/tcp closed' % tgtPort
	finally:
		screenLock.release()
		connSkt.close()

def portScan(tgtHost, tgtPorts):
	try:
		tgtIP = gethostbyname(tgtHost)
	except:
		print "[-] Cannot resolve '%s': Unknown host" % tgtHost
		return

	try:
		tgtName = gethostbyaddr(tgtIP)
		print '\n[+] Scan Results for : ' + tgtName[0]
	except:
		print '\n[+] Scan Results for: ' + tgtIP

	setdefaulttimeout(1)
	for tgtPort in tgtPorts:
		t = Thread(target=connScan, args=(tgtHost, int(tgtPort)))
		t.start()

def main():
	parser = optparse.OptionParser('usage%prog ' + \
		' -H <target host> -p <target port>')
	parser.add_option('-H', dest='tgtHost', type='string', \
		help='specify target host')
	parser.add_option('-p', dest='tgtPort', type='string', \
		help='specify target port[s] separated by comma')
	(options, args) = parser.parse_args()
	tgtHost = options.tgtHost
	tgtPorts = str(options.tgtPort).split(',')
	if (tgtHost == None) | (tgtPorts[0] == None):
		print parser.usage
		exit(0)
	portScan(tgtHost, tgtPorts)

if __name__ == "__main__":
	main()
